There is only one file type that uses the .NQC extension:
Not Quite C Source Code File
Source code file written in the Not Quite C (NQC), a programming language used to program LEGO MINDSTORMS products such as the RCX, CyberMaster, and Scout; contains instructions that control the motion and other actions of a robot's bricks.
NQC files can be compiled using the NQC compiler and then uploaded to the robot. Compiled files are uploaded via USB connection using the LEGO software. The NQC compiler is included with Bricx Command Center (BricxCC), an IDE used for programming the robot bricks.
NOTE: LEGO MINDSTORMS is a line of LEGO products that contains advanced programmable pieces that enable robot construction and motion.
Updated: September 21, 2010